plat: marvell: Add support for Armada-37xx SoC platform

Add supprot for Marvell platforms based on Armada-37xx SoC.
This includes support for the official Armada-3720 modular
development board and EspressoBin community board.
The Armada-37xx SoC contains dual Cortex-A53 Application CPU,
single secure CPU (Cortex-M3) and the following interfaces:
- SATA 3.0
- USB 3.0 and USB 2.0
- PCIe
- SDIO (supports boot from eMMC)
- SPI
- UART
- I2c
- Gigabit Ethernet

Signed-off-by: Konstantin Porotchkin <kostap@marvell.com>
diff --git a/include/plat/marvell/common/mvebu.h b/include/plat/marvell/common/mvebu.h
index a20e538..a7d6c3f 100644
--- a/include/plat/marvell/common/mvebu.h
+++ b/include/plat/marvell/common/mvebu.h
@@ -32,7 +32,8 @@
 #define ROUND_UP_TO_POW_OF_2(number)	(1 << \
 					(32 - __builtin_clz((number) - 1)))
 
-#define _1MB_				(1024ULL*1024ULL)
-#define _1GB_				(_1MB_*1024ULL)
+#define _1MB_				(1024ULL * 1024ULL)
+#define _1GB_				(_1MB_ * 1024ULL)
+#define _2GB_				(2 * _1GB_)
 
 #endif	/* MVEBU_H */